Name of Session: Cancer Screening (Mutants Welcome!)

Session Leaders:
Joy

Length of Session:
Part 1 (Day 1): 30 minutes
Part 2 (Day 4): 45 minutes

Learning Goals for DVI Fellows:
The learner will:
· Realize the effects of DNA-damaging UV rays and the importance of sun screen (Part 2).
· Understand what a DNA mutation is, how nucleotide alterations occur, and why changes in gene expression can have adverse effects (Part 2).
· Draw connections between mutagens, DNA damage, and cancer, while keeping in mind that not all damage leads to cancer (Part 2).
· Be able to explain that not all DNA mutations are detrimental and how these benign mutations can be used in forensic investigations (Part 2).

Summary of Activities:
Materials Required:
Wildtype yeast strain
Mutant yeast strain
Yeast plates
UV light source
Sunscreen, sunglasses, plastic wrap, etc.

Session Overview:
Engage
· Fellows will evenly distribute two different yeast strains on four agar plates (two plates for each strain). One of each plate will be left undisturbed as controls. The other two plates will be exposed to UV light to illustrate the damaging properties of sunlight. Alternatively, some fellows may choose to expose both their control and experimental plates to UV, but use sunscreen, sunglasses, plastic wrap, etc. to “protect” their experimental plates (Part 1).

Explore
· Fellows will observe the yeast growth on each of their plates after several days of growth, comparing the control plates to the experimental plates (Part 2).

Explain
· In a sharing-out session, fellows will discuss the results of their experiment, comparing their control plates to their experimental plates. The fellows may have set-up different experiments so the sharing-out session will allow them to hear about the results of other groups’ experiments (Part 2).

Elaborate
· The fellows will use four different colored paper clips to simulate how nucleotide changes occur and discover how differences between individuals arise (at the molecular level). A brief discussion regarding the forensic applications of unique DNA patterns will be included as the fellows continue to use their paperclip chains to simulate RFLP analysis (Part 2).
· The nature of the mutation in the mutant yeast strain (deletion of gene in a DNA repair pathway) will be discussed and the fellows will be asked to draw conclusions as to why the two yeast strains faired differently in the experiment (Part 2).
· Connections will be made between nucleotide changes, altered gene expression, and the health/viability of an organism—the fellows will be asked to explain how mutations can be neutral, advantageous, or disadvantageous and how this relates to species survival (Part 2).



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